NH9.6 | Consequences of natural hazards: Costs and impacts on infrastructure and natural and built heritage
EDI
Consequences of natural hazards: Costs and impacts on infrastructure and natural and built heritage
Convener: Maria Bostenaru Dan | Co-conveners: Lukas Schoppa, Adrian Ibric, Nurullah Bektaş, Veit Blauhut, Margherita D Ayala, Nadja Veigel
Orals
| Thu, 18 Apr, 08:30–10:15 (CEST)
 
Room 0.15
Posters on site
| Attendance Thu, 18 Apr, 10:45–12:30 (CEST) | Display Thu, 18 Apr, 08:30–12:30
 
Hall X4
Posters virtual
| Attendance Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X4
Orals |
Thu, 08:30
Thu, 10:45
Thu, 14:00
The session aims to gather views on consequences of natural hazards, especially their costs as well as their impacts on infrastructure and natural and built heritage.
On the one hand, the session aims to highlight the challenges and advances in assessing the costs of natural hazards (e.g., storm, floods, droughts, earthquakes, fire) around three main topics: post-event data collection, assessment methods, and economic evaluation of risk management measures. The session will address methodological and empirical aspects of data collection and evaluation of various types of costs (direct damage, indirect damage, health impacts, risk reduction costs, environmental). We are interested in contributions that are concerned with both theoretical and practical aspects such as economic appraisal, risk reduction and transfer, adaptation, or dynamics of vulnerability and resilience.
On the other hand, the session addresses disaster risk management affecting built and natural heritage as a consequence of natural and human-made hazards. The whole disaster risk management cycle is covered in a sustainability and resilience approach, from preparedness and mitigation to emergency and rebuild. Particularly welcome are contributions addressing digital methods to map the impact of these hazards on heritage, at both object scale and at the larger neighbourhood, urban and regional scale, including the interaction between these levels. Both contributions addressing methods and lessons learned from case studies are welcome. Possible approaches include how the civil protection and urban planners use this knowledge for decisions. Apart of addressing decision stakeholders per se, the development of decision systems with the integrated scope of addressing (landscape) architectural and archaeologic heritage using digital methods are particularly welcome. Benefit-costs analysis must be part of any decision tree.

We would like to invite potential abstract authors to submit a full paper to the special issue: NHESS – Special issue – Natural hazards’ impact on natural and built heritage and infrastructure in urban and rural zones (https://nhess.copernicus.org/articles/special_issue1252.html).

Orals: Thu, 18 Apr | Room 0.15

Chairpersons: Lukas Schoppa, Nurullah Bektaş, Maria Bostenaru Dan
08:30–08:35
Geophysical hazards
08:35–08:45
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EGU24-18463
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On-site presentation
Giorgia Giardina, Elpida Georgiou, Raymond Brouwers, Dominika Malinowska, Max Hendriks, and Pietro Milillo

Cultural heritage sites all over the world are increasingly threatened by regional-scale subsidence. Addressing this issue necessitates a deep understanding of how ground settlements impact structural integrity. Traditional approaches, primarily reliant on in-situ investigations, are not only costly but also constrained by their installation in anticipated vulnerable structures. Recent advances in satellite technologies, historically used in geophysical studies of natural phenomena like glaciers and earthquakes, have shown potential in detecting structural deformations. In particular, Interferometric Synthetic Aperture Radar (InSAR) techniques have the capability to measure ground subsidence and building displacements with millimetric precision, they are independent from weather and light conditions, and can provide frequent, weekly updates over extensive areas. Furthermore, the availability of historical data enables retrospective monitoring, eliminating the requirement for pre-installed in-situ monitoring systems. Nevertheless, the interpretation of InSAR data in isolation falls short without correlating it to structural damage.

This study aimed to bridge the existing gap by integrating InSAR monitoring with Finite Element Method (FEM) modelling, specifically applied to a historic church in Poland affected by mining-induced ground settlements. The objective was to predict the structural damage over time caused by subsidence at this heritage site. InSAR data for a reference region, including the area around the church, was acquired and processed using Multi-Temporal InSAR techniques. This was complemented by regional-scale interpolation to address data gaps near the church. These displacement measurements were then incorporated into a computational model of the church, to estimate the level of structural damage. The FEM model, informed by InSAR-derived displacements, was used to assess the impact of various factors on the church's structural response. These factors included settlement profiles and soil-structure interaction characteristics. Through the proposed integration, we aimed to gain critical insights into the resilience of cultural heritage sites and develop novel, practical tools for analysing structures at risk.

How to cite: Giardina, G., Georgiou, E., Brouwers, R., Malinowska, D., Hendriks, M., and Milillo, P.: Assessing subsidence-induced damage on heritage: an integrated remote sensing and structural modelling approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18463, https://doi.org/10.5194/egusphere-egu24-18463, 2024.

08:45–08:55
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EGU24-18163
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ECS
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On-site presentation
Tara Evaz Zadeh, Max Wyss, and Danijel Schorlemmer

Disaster preparedness and risk reduction is one of the most valuable research topics from both seismological and societal aspects to save lives. Scenario loss assessments help disaster managers to conceive an idea about what to expect and how to best prepare for the disaster. Prior to providing such scenario loss estimates, it is imperative to conduct an evaluation of the utilized program and its method. In the absence of information regarding the reliability of the assessments, an evaluation of potential future losses becomes challenging and even unreliable.

There are multiple tools available for rapid earthquake loss estimation purposes. 'Quake Loss Assessment for Response and Mitigation' (QLARM) is one of the few established programs, existing since 2002. It is a computer program used by the International Centre for Earth Simulation in Geneva, Switzerland, to issue timely reports on both building damage and human losses for potentially damaging earthquakes. QLARM uses 2013 population information for approximately 2 million settlements world-wide along with the building information initially taken from the World Housing Encyclopedia. These settlements are then classified into distributions of building vulnerabilities according to the six classes in EMS98 and seismic intensity fields are estimated for each earthquake to compute the expected losses. 'Loss-Calculator' on the other hand, is a new Python program that employs a different approach than QLARM. It uses detailed building-by-building information along with the population assigned to each building based on the buildings’ size and types. The buildings in the Loss-Calculator are classified into numerous classes, following the taxonomy of the Global Earthquake Model. Losses are computed based on ground-motion fields using standard intensity measures like peak ground acceleration (PGA) or spectral accelerations (SA).

We first evaluate the accuracy of both tools for several destructive past earthquakes to explore the uncertainty range of results and identify potentially necessary calibration or improvements in the input data, e.g. the earthquake shaking, population numbers, settlement and building locations. To focus on relevant events with a high death toll, we selected earthquakes in Iran, such as the Rudbar-Manjil (Mw=7.4) and the Qayen (Mw=7.3) earthquakes with fatalities of around 40,000 and 1,500, respectively. This comparison includes not only the absolute value of the losses, but also their detailed spatial distribution. We also compare the loss assessments using different possible inputs, such as different building information and intensity measure fields to achieve the goals.

Furthermore, we estimate losses expected to occur in possible future earthquakes by computing probable earthquake scenarios. These scenarios prove the need for serious disaster preparation and highlight the likely locations of largest losses or most affected people. We introduce high-resolution spatial distributions of losses for improved disaster preparedness planning and show how the detailed knowledge of building locations can improve loss assessments.

How to cite: Evaz Zadeh, T., Wyss, M., and Schorlemmer, D.: Earthquake loss assessments methods - Comparison and new developments shown on past and future earthquake scenarios for Iran, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18163, https://doi.org/10.5194/egusphere-egu24-18163, 2024.

08:55–09:05
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EGU24-22242
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On-site presentation
Max Wyss

Three major earthquake disasters occurred during 2023: Turkey M7.8, February 6, Morocco M6.8 August 9, Afghanistan M6.5 November 10. The final cost in lives reported were 59500, 2946 and 1482 fatalities, respectively. QLARM (Quake Loss Alerts for Recovery and Mitigation) is a computer tool used to estimate damage, fatalities and injured for potentially fatal earthquakes worldwide. Using QLARM (e. g. Wyss 2014, 2023), my estimates were the only red alerts for these earthquakes issued within minutes. Red alerts are the highest level of urgency that can be given. The fatality estimates were 2000-6000 for Turkey, 100 to 1000 for Morocco, and a total of 500 to 2000 for the Afghanistan earthquake swarm (three messages within 4 days). These alerts were distributed by SMS to anyone who signed up to receive the QLARM alerts (signup link given below) free of charge. These three red alerts were received by subscribers within 30, 31, and 18 minutes, respectively. The USGS hypocenter and magnitude estimates arrived within 29, 24 and 30 minutes, respectively. The QLARM fatality estimates were based on the first information on source parameters for these three earthquakes available worldwide, which came from GFZ (Geophysicalisches ForschungsZentrum, Potsdam) after 7, 8 and 7 minutes, respectively.

The purpose of the QLARM alerts is to activate first responders and government in case of earthquake disasters, and also to furnish quantitative information for the many large magnitude earthquakes that were not likely to have killed many and therefore for which an international response was not needed. During the year 2023, QLARM issued a total of 60 alerts with a median delay of 22 minutes.

The chief reason for the initial fatality underestimates for the Turkey and Morocco disasters was that the source was assumed to be a point, which was appropriate only for the Afghanistan sequence, where the fatality estimate was correct. The information on the lengths, direction and endpoints of the rupture became available only later for the Turkey and Morocco cases. Using line sources for the Turkey and Morocco earthquakes brings the fatality estimates closer to the reported ones, but they are still lower than what was reported, most likely due to the construction of buildings in these two regions, which are apparently weaker than assumed in the QLARM data set. The most important means of improving near-real-time estimates of earthquake losses is to implement rapid estimates of rupture lengths and azimuths.

References:

International Centre for Earth Simulation (ICES). QLARM sign-up. https://www.icesfoundation.org/Pages/CustomPage.aspx?ID=122, Retrieved January 09, 2024.

Wyss, M. (2014). Ten years of real-time earthquake loss alerts. In Earthquake hazard, risk and disasters (pp. 143-165). Academic Press.

Wyss, M. (2023). Quantitative Earthquake Loss Estimates the New Frontier. Seismological Research Letters, 94(6), 2569-2574.

How to cite: Wyss, M.: Estimates of the number of fatalities within minutes for the three great earthquake disasters in 2023, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22242, https://doi.org/10.5194/egusphere-egu24-22242, 2024.

Meteorological hazards
09:05–09:15
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EGU24-20225
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Highlight
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On-site presentation
Normalized Hurricane Damage in the United States: 1900-2022
(withdrawn)
Joanne Muller, Kaylee Mooney, Steven Bowen, Philip Klotzbach, Tynisha Martin, Tom Philp, Dhruvkumar Bhatt, and Richard Dixon
Hydrological hazards
09:15–09:25
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EGU24-18789
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ECS
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On-site presentation
Guilherme Samprogna Mohor and Annegret Thieken

The documentation and quantification of flood impacts is required by multiple actors, such as public administrators, insurers and scientists, for multiple reasons, such as planning, mitigating, projecting or even forecasting. Collecting and analysing impact data is however not systematically undertaken. Direct flood impacts can be documented as structural (or physical) or financial damage. Structural damage is described as an ordered classification with five grades, from moist and dirt, to wall cracking, up to complete collapse. The financial damage is rather documented as absolute or relative damage, i.e. the ratio between repair costs and the building value, which allows for an easier comparability. Both structural and financial damage are at times documented and numerical models have been developed for both types. Models are frequently used to estimate damage of undocumented cases and make projections. Yet, large uncertainties remain and each model has different data requirements, making them sometimes inapplicable for a certain area or after a certain flooding event. In a joint work, we have shown that the documentation of structural damage need not be undertaken on site, but can be accomplished for large areas through remote sensing, when quality aerial data is available. Here, we also explore the relationship between the two impact types, structural and financial damage, to allow for a conversion from structural to financial damage, complementing the data gathering obviating the labour- and time-intensive on-site surveys. The work is based on survey data gathered after eight flood events in Germany. The data can be regarded representative and transferable to Europe as most buildings are of masonry and have a cellar.

How to cite: Samprogna Mohor, G. and Thieken, A.: Developing structural-financial flood damage curves for residential buildings, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18789, https://doi.org/10.5194/egusphere-egu24-18789, 2024.

09:25–09:35
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EGU24-1041
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ECS
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Highlight
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On-site presentation
Apoorva Singh, Nivedita Sairam, Kasra Rafiezadeh Shahi, Anna Buch, Chandrika Thulaseedharan Dhanya, and Heidi Kreibich

Flash floods like the flood in 2021 in the west of Germany result in particularly large numbers of fatalities and heavy asset damages. Among the several flood-exposed sectors, companies are severely affected by floods and constitute a significant component of overall flood damages. However, understanding and modeling the underlying processes influencing flash flood losses for companies is specifically challenging due to (1) heterogeneity in terms of sectors, building size and type, number of employees, and equipment, and (2) scarcity of company-specific flood loss data. In comparison to fluvial floods, the influence of flood characteristics and hydro-dynamic processes on damage is different in the case of flash floods.  To tackle this challenge, multi-variate probabilistic flash flood loss models are developed based on feature selection using empirical data from detailed surveys conducted with companies after the flash floods of 2002, 2016, and 2021 in Germany. The machine learning ensemble-based approach of feature selection revealed the significance of the following hazard variables (water depth, flow velocity, contamination), exposure variables (sector, number of employees, size of premise), and vulnerability variables (implementation of precautionary measures, early warning time, flood experience) in determining flood losses. The Bayesian Networks-based flood loss models developed in this study provide probability distributions of estimated losses and as such inherently quantify uncertainties.

How to cite: Singh, A., Sairam, N., Shahi, K. R., Buch, A., Dhanya, C. T., and Kreibich, H.: AI based assessment of flash flood damages to company, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1041, https://doi.org/10.5194/egusphere-egu24-1041, 2024.

09:35–09:45
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EGU24-17113
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ECS
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On-site presentation
Marta Ballocci, Daniela Molinari, Francesco Ballio, Giovanni Marin, Alice Gallazzi, and Panagiotis Asadiris

Flood-related damage has increased dramatically in recent decades with direct and indirect economic impacts accounting for a large share of gross national products. Therefore, there is an urgent need to acquire more quantitative knowledge about flood damage to mitigate economic losses and reduce exposure to flood risk.

Firms are especially affected in case of flood. Still, flood direct damage assessment to businesses is hindered by the paucity of available data to characterize the enterprises, the lack of high-quality damage data to derive new models or validate existing ones, and the high variability of activity types which hampers generalization. On the indirect damage side, the existing literature predominantly focus on estimating damage at the macro scale, leaving a gap in understanding the specific impact on individual firms.

This study contributes at improving knowledge about types and extent of damage of flood events on economic activities through the analysis of empirical data, focusing on direct and indirect damage at the micro-scale, with specific reference to the Italian context. The investigated data derive from observed direct damage records collected after six flood events in Italy. The information on the surface of the building, the typology of the affected firms (i.e., NACE category) as well as on local water depth levels and the classification in damage components (building, equipment, and stock) permitted to develop an econometric model to forecast the direct damage and to analyze the mechanisms of flood damage across the economic sectors. The original dataset was then enriched with information included in the financial statement of flooded activities that has been used to investigate indirect damage.

Despite characterized by significant uncertainty, obtained results supply first tools for the prediction of flood direct damage and for the quantification of indirect damages to firms for the Italian context, in the support of more effective risk mitigation actions. In fact, the model identifies the more vulnerable elements within the business sectors orienting modelers and decision-makers choices.

How to cite: Ballocci, M., Molinari, D., Ballio, F., Marin, G., Gallazzi, A., and Asadiris, P.: New tools for the estimation of direct and indirect impacts to Italian economic activities, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17113, https://doi.org/10.5194/egusphere-egu24-17113, 2024.

09:45–09:55
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EGU24-12992
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ECS
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Highlight
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On-site presentation
Elisa Grazia Lucia Nobile, Marcello Arosio, Alessandro Caiani, Jlenia Di Noia, and Mario Lloyd Virgilio Martina

Climate change and urbanization are intensifying economic losses from natural hazards, particularly floods, making robust risk assessment crucial. However, traditional risk assessment frameworks fall short in representing the full costs of natural hazards, as they typically focus only on direct damages, like property damages, neglecting the indirect tangible damages. One of the key objectives of this research is to quantify the indirect economic impacts resulting from business interruption (i.e. reduction in production due to physical damages in areas directly affected by the hazard) and contingent business interruption (i.e. production losses of suppliers and customers of companies directly affected by the hazard), and the associated macroeconomic impact. This study addresses this gap by employing a multidisciplinary approach, integrating network theory with traditional Input-Output (I-O) economic models. This integration not only enhances the representation of the interconnectedness inherent in socio-economic systems but also aids in quantifying the often-overlooked indirect effects of floods. The methodology integrates high-resolution input-output tables, geolocalized firms and spatial information on critical infrastructures, like the transportation network. This comprehensive approach not only provides a detailed view of the cascading economic effects, but it could also enhance traditional I-O models by incorporating information on geographical substitutability. The detailed understanding of economic dependencies and network vulnerabilities is crucial in assessing the full costs of floods. Applied to a significant Italian region recently struck by a severe flood, the approach allows for the mapping of the region's economic structure as an interconnected network of economic sectors. Network theory measures and tools are then employed to identify central and vulnerable nodes, enabling a detailed analysis of shock propagation within supply chains. The findings of this research are not only critical for policy-makers and urban planners in adopting more effective flood risk management strategies but also offer valuable insights for the insurance sector in terms of understanding and mitigating collective risk. In conclusion, this study advocates for a shift from traditional risk assessment models towards a more holistic, systemic approach, thereby enhancing societal resilience to the multifaceted impacts of natural hazards.

How to cite: Nobile, E. G. L., Arosio, M., Caiani, A., Di Noia, J., and Martina, M. L. V.: Quantifying the Economic Impact of Floods on Businesses with a Network Analysis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12992, https://doi.org/10.5194/egusphere-egu24-12992, 2024.

09:55–10:05
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EGU24-19185
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ECS
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Virtual presentation
David Nortes Martínez, Frédéric Grelot, Pascal Finaud-Guyot, Marie Arragon, and Freddy Vinet
In France, adaptation to floods has been the subject of a clearly identified public policy, at least since the first versions of the action programs for flood prevention launched in 2002. Axis 5 of these action programs aims to reduce the vulnerability of people and property by implementing flood adaptation measures at the "individual" level, i.e. dwellings, economic or agricultural activities.

In the specific case of dwellings, flood adaptation can have two objectives: to increase human safety and to reduce material damage. Neither of these objectives has an established method for measuring the effectiveness of the recommended measures. In fact, although it has been identified as a priority, the evaluation of the effectiveness of proposed measures remains underdeveloped and, as a consequence, professionals, especially those performing vulnerability assessments, lack the tools to assess the validity of their recommendations.
Furthermore, a number of studies show that effectiveness assessment can call into question the very validity of programs that are designed on the basis of broad principles but applied to specific areas.

This work presents an original spatially explicit, process-based (synthetic) 3D model at the building level, combining hydraulic and economic modules, and we show how it can respond to this need for assessing the effectiveness of flood adaptation measures. This model relies on the characterization of the vulnerability of spatially explicit (xyz) elementary building components based on expert knowledge and on the classical weir law to determine the water flow exchange between the exterior and interior of a building and between rooms. The combination of these elements allows us to i) simulate the hydraulic behavior of the building using flood duration and exterior flood depth as the main flood parameters; ii) estimate the flood damage caused by a flood event; and iii) dynamically evaluate the danger of the path(s) to safety inside the building based on pedestrian stability studies.
Real case buildings are used to test the model. The selected buildings benefited from a French vulnerability reduction program called "Alabri". This program offers vulnerability diagnostics of buildings to voluntary owners and, based on the diagnostics, recommendations for vulnerability reduction. Field work and interviews show that the most frequently proposed measures are aimed at preventing water infiltration inside buildings (with temporary barrier systems) and creating refuge areas for people. The hypothesis is that the combination of both measures is sufficient to reduce flood damage and ensure the safety of the occupants of a dwelling. We also use specific hydraulic conditions to test these measures and their combination.

This approach allows us to perform contextual analyses and provide insights into the effectiveness of the recommended measures and their combination. This approach also allows us to analyze the extent to which the methodology we propose is consistent with the approach chosen by the professionals who carried out the diagnoses. Finally, it allows us to explore the potential of synthetic models for the ex ante analysis of mitigation policies.

How to cite: Nortes Martínez, D., Grelot, F., Finaud-Guyot, P., Arragon, M., and Vinet, F.: Contribution of coupling hydraulic and economic models at the building scale for assessing flood adaptation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19185, https://doi.org/10.5194/egusphere-egu24-19185, 2024.

10:05–10:15
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EGU24-10267
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On-site presentation
Nandini Suresh, Trupti Mishra, and Devanathan Parthasarathy

Disasters have significant environmental, human, social, economic, and financial impacts. These effects are potentially long-lasting and have multi-generational consequences. Due to climate change, disasters have cascading and compound effects, heightening the financial risks. However, the number of countries issuing CAT Bonds as a financial instrument for tackling the financial burden of disasters is less than 5% as of 2023. This study explores the need to use CAT Bonds as a risk transfer mechanism that allows governments and insurers to spread their climate change risk across capital markets. It presents a comprehensive cross-country level analysis of the potential drivers that influence the CAT bond issuance at a sovereign level for 131 countries from 2016 to 2021 to understand their significance for issuers and non-issuers of CAT Bonds. These potential drivers were filtered after an exploratory factor analysis. Nonetheless, the imbalance between the number of issuers and non-issuers has resulted in poor classification accuracy results and bias. Hence, this study employs Logistic Regression with Synthetic Minority Over-sampling Technique (SMOTE) and without SMOTE. Further, a comparison study between the effective CAT Bond issuance in the Philippines against non-issuance in India was conducted to determine the obstacles in the Indian setting. The result from the study indicates that a country’s exposure to hazards, population growth, investment freedom, regulatory quality, gross budget balance, stock traded and rule of law have statistically significant impact on the issue of CAT Bond. Highlighting the Indian context, the major challenges the country faces in issuing CAT Bonds are its stringent rule of law, regulatory inferiority, economic uncertainty, and less stock traded.

How to cite: Suresh, N., Mishra, T., and Parthasarathy, D.: Catastrophic (CAT) Bond as Sustainable Finance Instruments: Understanding from Cross-Country Perspectives, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10267, https://doi.org/10.5194/egusphere-egu24-10267, 2024.

Posters on site: Thu, 18 Apr, 10:45–12:30 | Hall X4

Display time: Thu, 18 Apr, 08:30–Thu, 18 Apr, 12:30
Chairpersons: Lukas Schoppa, Nadja Veigel
Geophysical/geological hazards
X4.160
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EGU24-1012
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ECS
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Highlight
Nurullah Bektaş

Seismic safety assessment of existing buildings is very important because their design and construction are made according to lower standards. The buildings designed with lower standards and without standards are susceptible to earthquake-induced damage. The vulnerability of existing buildings to seismic events has been vividly highlighted by recent earthquakes, such as the Türkiye–Syria earthquake on February 6, 2023, the Herat Afghanistan earthquake on October 11, 2023, and the Marrakesh-Safi Morocco earthquake on September 9, 2023. In the Turkey-Syria earthquake alone, over 50,000 people lost their lives [1], over 100,000 sustained injuries [2], and the economic toll amounted to approximately 110 million dollars [3]. Building damage from seismic events poses risks to lives and causes substantial financial losses, necessitating the determination of each building's fragility and the implementation of appropriate precautions before an impending devastating earthquake. Rapid Visual Screening (RVS) methods are employed for assessing building inventory, given the computational and cost constraints of in-depth vulnerability assessment methods. While conventional RVS methods are widely used and high efforts are given to enhance them, their reliability is limited for accurately assessing a building inventory [4–6]. Therefore, this study leverages post-earthquake building inspection data from the 2015 Gorkha, Nepal earthquake to develop a RVS method using artificial intelligence algorithms, encompassing fuzzy logic, machine learning, and neural networks. The integration of advanced feature engineering techniques introduces sophisticated parameters like fundamental structural period, spectral acceleration, and distance to the earthquake source, enhancing the RVS method's assessment capabilities across diverse seismically vulnerable areas. The developed RVS method demonstrates a correlation between observed building post-earthquake damage states and the predicted ones. When compared to conventional RVS methods, a noteworthy test accuracy of 44% is achieved, surpassing conventional methods in accurately classifying building damage states. Notably, in contrast to RVS methods solely developed using machine learning and neural networks, the developed method exhibits transparency and the capability to be adapted to different regions.

Keywords:

Seismic vulnerability assessment; Earthquake-induced damage; Rapid Visual Screening (RVS); Artificial intelligence algorithms; Fuzzy logic; Machine learning; Neural networks

 

References: 

[1]        UN says at least 50,000 killed in Turkey and Syria quakes, AP News. (2023). https://apnews.com/article/turkey-syria-earthquakeunited-nations-44c2b736108ccb37130cf64e9e5fa7ca (accessed December 1, 2023).

[2]        Turkey and Syria earthquake: latest news, British Red Cross. (n.d.). https://www.redcross.org.uk/stories/disasters-and-emergencies/world/turkey-syria-earthquake (accessed December 1, 2023).

[3]        M. Ozturk, M.H. Arslan, H.H. Korkmaz, Effect on RC buildings of 6 February 2023 Turkey earthquake doublets and new doctrines for seismic design, Engineering Failure Analysis. 153 (2023) 107521. https://doi.org/10.1016/j.engfailanal.2023.107521.

[4]        N. Bektaş, F. Lilik, O. Kegyes-Brassai, Development of a fuzzy inference system based rapid visual screening method for seismic assessment of buildings presented on a case study of URM buildings, Sustainability. 14 (2022) 27.

[5]        N. Bektaş, O. Kegyes-Brassai, Development in Machine Learning Based Rapid Visual Screening Method for Masonry Buildings, in: M.P. Limongelli, P.F. Giordano, S. Quqa, C. Gentile, A. Cigada (Eds.), Experimental Vibration Analysis for Civil Engineering Structures, Springer Nature Switzerland, Cham, 2023: pp. 411–421. 

[6]        E. Harirchian, T. Lahmer, Developing a hierarchical type-2 fuzzy logic model to improve rapid evaluation of earthquake hazard safety of existing buildings, Applied Sciences (Switzerland). 10 (2020) 1384–1399.

How to cite: Bektaş, N.: Enhancing Seismic Safety Assessment Through Development of a Transparent and Adaptive Rapid Visual Screening Method Employing Artificial Intelligence Algorithms, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1012, https://doi.org/10.5194/egusphere-egu24-1012, 2024.

X4.161
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EGU24-18643
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Highlight
Stavroula Alatza, Nikolaos Stasinos, Nikolaos Stathopoulos, Marietta Papakonstantinou, Michail-Christos Tsoutsos, and Charalampos Kontoes

The Western Greece is one of the most tectonically active regions in the Mediterranean Sea, due to the subduction of the African plate underneath the Eurasian plate. The past years, major earthquakes occurred in Western Greece, causing destructions and casualties. Ancient Olympia, located in the North West of the Peloponnese in Western Greece, combines a great cultural background with natural beauty and is also associated with the Olympic Games. It is among the most visited archaeological sites in Greece, as it combines cultural tourism, eco-tourism and sports tourism. However, the complex tectonic field of Western Greece, including the broader area around Ancient Olympia, raises awareness and dictates the adoption of preventive and recovery measures in case of an earthquake risk in Western Peloponnese. Therefore, we propose an emergency and recovery plan for an earthquake risk scenario, that will be implemented in the broader area around the archaeological site of Ancient Olympia. Satellite and geospatial data are processed to extract all necessary thematic information. Additionally, multi-temporal InSAR analysis of Sentinel-1 images, is performed to identify areas exposed to ground deformation phenomena, therefore vulnerable during an earthquake. Detailed thematic information layers, combined with the identification of ground instabilities in the wider area around Ancient Olympia, will contribute to an efficient evacuation and reconstruction plan. Since cultural heritage sites are often exposed to various hazards, including geohazards, preparedness, risk assessment and emergency management near cultural heritage sites, is of great importance for their protection and preservation.

 

Acknowledgements

The research was funded by the Working Programme 2021 under the Caroline Herschel Framework Partnership Agreement on Copernicus User Uptake.

How to cite: Alatza, S., Stasinos, N., Stathopoulos, N., Papakonstantinou, M., Tsoutsos, M.-C., and Kontoes, C.: Geospatial and remote sensing analysis for earthquake risk management: The case study of Ancient Olympia archaeological site. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18643, https://doi.org/10.5194/egusphere-egu24-18643, 2024.

X4.162
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EGU24-17355
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ECS
Guidelines Of Indicator Based Landslide Vulnerability Analysis and Risk Classification for Critical Infrastructure in Malaysia
(withdrawn after no-show)
Yusrin Faizd Abd Wahab, Mohd Khairolden Ghani, Muhammad Zulkarnain Abdul Rahman, Zakaria Mohamad, Ferdaus Ahmad, Che Hassandi Abdullah, and Mastura Azmi
X4.163
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EGU24-17388
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ECS
Enrico Ciracì, Carmine Frascella, Filippo Santarelli, Emanuela Valerio, Stefano Scancella, and Andrea Chessa
In this study, We use data from the European Space Agency Sentinel-1 mission to map areas affected by active deformation processes over the Italian territory. To achieve this goal, we use data acquired by the satellite mission between 2018 and 2023, and we generate ground deformation products using a multi-temporal interferometric approach (Persistent Scatterer Interferometry - PS).
We automatically delimitate areas characterized by homogeneous deformation by employing a novel spatial clustering algorithm that analyzes the PS average annual displacement rate over the considered temporal period. For each cluster, we determine its boundaries and average deformation statistics.
Here, we present the algorithm implementation details and discuss the results obtained by applying the methodology to deformation observations acquired from ascending and descending geometries and projected 2D East-West and Vertical deformation products. We use the algorithm to process observations acquired over two validation sites, and we determine its performance over large spatial scales and in proximity to critical national infrastructures.
Our results allow us to generate a complete, nationwide dataset of active deformation areas, highlighting how adopting automatic strategies to handle large volumes of data is crucial nowadays.

How to cite: Ciracì, E., Frascella, C., Santarelli, F., Valerio, E., Scancella, S., and Chessa, A.: Mapping of Active Deformation Areas using Multi-Temporal InSAR data., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17388, https://doi.org/10.5194/egusphere-egu24-17388, 2024.

Hydrological hazards
X4.164
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EGU24-10438
Maria Bostenaru Dan

In the 20th century often the solution to mitigate floods was putting a corset of reinforced concrete to rivers. An example is one of the case studies in our project which we will detail, the Vidraru dam on Arges river, where a neighbourhood was built after the 1940 floods. In the 21st century however the approach is different. Several years ago a communication session was dedicated to achieving more flood resilience through floodplains on the Danube, and also several years ago a doctorate was concluded on landscape architecture solutions to mitigate floods on the Rhine. The geographic areas are different, and so are the localities and the early 20th century constructions which might be affected by floods and their relationship to the city - ex. peripheral Siedlung in Germany. Today one can look more systematically. A recent course of the European Commission offered insights to natural disaster mitigation through nature based solutions across the globe. We also reviewed literature in a nice part of this: decision systems to prioritise interventions based on cost-benefit to mitigate floods. On this basis, identifying gaps - the papers cover some of the aspects of this issue at once, not all of them - we elaborated a decision tree and its taxonomy according to criteria related to the building and the river landscape. The indices to quantify these criteria will be shown. This will be exemplified in case studies comprising Bucharest, Rome and Lisbon. It can be converted into an ontology for software planning, as in numerous European projects related to protection of architectural and archaeological heritage protected from climate change with IT support which go even further, towards Internet of Things. The context of future possible projects will be shown in the discussion.

How to cite: Bostenaru Dan, M.: Decision systems for nature based solutions to mitigate floods, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10438, https://doi.org/10.5194/egusphere-egu24-10438, 2024.

X4.165
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EGU24-11615
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ECS
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Highlight
Claudia De Lucia, Fabio Castelli, and Chiara Arrighi

Floods are among the most frequent and damaging events worldwide, affecting population and residence buildings, economic activities, agriculture but also cultural heritage (hereinafter CH). Flood impacts to CH are very challenging to evaluate, due to their intangible values (e.g., spiritual, social, aesthetic) and difficulty in replacing unique objects. These aspects make the evaluation of CH exposure and vulnerability complex, also depending on the scale of analysis adopted.

This work aims at illustrating the differences in risk evaluations, as the scale of analysis varies. It highlights the information usually available for flood risk analysis of CH when moving from a large scale, e.g. regional/national level, to building scale, with different stakeholders’ perspectives, and demonstrates a very detailed approach for hazard modelling inside the CH building. The regional/national scale considers CH often as a point feature and usually aims at identifying geographic damage hotspots, i.e., river basin authority perspective. Few information is available at this scale, mostly hazard classification (low to high probability of occurrence) and often a tailored taxonomy for exposed assets has to be developed.

The site/city scale usually considers cultural heritage as a polygon feature with a better description of flood depths and of building characteristics such as the building type (e.g., religious or rural), the presence of underground floors or the presence of artworks. It identifies risk priorities and potential damage, i.e. it adopts a mayors’ perspective.

The building scale analysis, i.e., heritage manager perspective, requires moving towards a 3D geometric description of the cultural building by incorporating elevations of features with respect to the terrain to better understand actual inundation depths and their effects. On-site inspections are required to measure specific characteristics of the structure such as the location and the height of the openings, which let floodwater enter inside the building. Such information allows for a downscaling of a city inundation model, that provides the hydrograph to assign as boundary condition to the building.

The method is applied to the Florence area (central Italy) and to a museum inside the city center. The 2D inundation model at building scale shows the inundation inside the basement of the museum, formerly a crypt, where a part of the permanent art collection is exhibited. The museum model reveals the flow and the quantity of water within different part of the building. A comparison with the historical records of the 1966 flood in the Museum, confirms the findings of the simulation.

Acknowledgments. This work received co-funding by (i) Regione Toscana, Fondo per lo Sviluppo e la Coesione 2014-2020, Project “GiovaniSì” and by (ii) the RETURN Extended Partnership, European Union Next-GenerationEU (National Recovery and Resilience Plan – NRRP, Mission 4, Component 2, Investment 1.3 – D.D. 1243 2/8/2022, PE0000005)

How to cite: De Lucia, C., Castelli, F., and Arrighi, C.: Flood risk to cultural heritage: a voyage through scales, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11615, https://doi.org/10.5194/egusphere-egu24-11615, 2024.

X4.166
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EGU24-4495
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ECS
Shou-Chi Chen, Kuo-Chen Ma, Mo-Hsiung Chuang, and Wen-Yen Lin

Amidst global climate change, extreme weather events are becoming increasingly common. The international community has established 'preventive conservation' of cultural assets as a core strategy. Nations are actively devising measures to counter the potential impacts of climate change on cultural assets and developing related adaptive strategies. Particularly noteworthy is the often-overlooked potential risk of natural disasters to cultural assets, which poses a severe threat to these irreplaceable assets.

This study focuses on the Kinmen area of Taiwan and utilizes data provided by the Taiwan Climate Change Projection and Adaptation Knowledge Platform (TCCIP). Employing flood risk maps as the primary analytical tool, it delves into the changing risks faced by cultural assets under climate change and explores how to implement preventive conservation strategies.

The research reveals that during the baseline period (1980-2015), Kinmen had 287 cultural assets, with 4 facing the risk of flooding. According to the extreme weather scenario AR5 (RCP 8.5) provided by TCCIP, it is predicted that various regions will experience more intense rainfall conditions in the mid-21st century (2041-2065), increasing the risk of flooding and leading to more cultural assets (18 in total) being threatened. Therefore, through meteorological data projection and disaster risk assessment, this study advocates for early preventive conservation measures for high-risk cultural assets, aiming to mitigate the potential impact of climate change on these valuable assets.

How to cite: Chen, S.-C., Ma, K.-C., Chuang, M.-H., and Lin, W.-Y.: Changes in Flood Risk to Cultural Assets Under Climate Change - A Case Study of  Kinmen, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4495, https://doi.org/10.5194/egusphere-egu24-4495, 2024.

X4.167
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EGU24-19500
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ECS
Federica Zambrini, Giovanni Menduni, and Sara D'Alessandro

Being able to quantify the possible flood damage in a territory is a pivotal matter while designing strategies to mitigate risk. In this context, data driven quick assessment can be an useful tool to better understand the territory needs and to establish priorities.

With our work we have been working on the spatial distribution of perceived flood damage in Italy, analyzing data coming from more than 45000 citizens’ declarations registered after events occurred in Italy between 2013 and 2021. We focused on events which required the national state of emergency, which activated the procedure of claims' collection carried out by regions. Working on such material, we’ve been able to identify the subset of data which are specifically associated to flood events and to geolocalize them. Once the definitive dataset was ready we had a framework of the perceived damage at square meter in the country, which has been analyzed at different spatial scales. The work highlighted a great variability and inhomogeinity within different areas in the country. A further step of the analysis tried to link the perceived damage to the characteristic of the society and the territory, explaining what drives the perception of damage.

How to cite: Zambrini, F., Menduni, G., and D'Alessandro, S.: Analysis of the spatial distribution of perceived flood damage in Italy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19500, https://doi.org/10.5194/egusphere-egu24-19500, 2024.

X4.168
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EGU24-31
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ECS
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Highlight
Weichen Zhong, Guy Howard, and Jeffrey Neal

Climate change and urbanization are expected to increase the risk of flood disasters in vulnerable areas. Urban road infrastructure can be affected by flooding, and subsequent restoration creates an additional carbon emission burden. These emissions are likely to compromise local decarbonization efforts, but there remains a lack of tools for quantifying the environmental impact of reconstruction projects after disasters. This study aims to develop an assessment framework to reveal the carbon footprint of post-flood road network restoration projects. The model integrates flood simulation, pavement damage evaluation, and carbon footprint calculation modules. This paper introduces nine flood scenarios ranging from 2-year to 1000-year events and a case study in Carlisle, UK, to test the integrated model. Results of the scenario simulation indicate that the carbon emissions from restoring per unit length of pavement as the flood magnitude increases for both main roads (10.46-19.21 kgCO2e) and low-volume roads (5.34-10.17 kgCO2e). Moreover, the case study indicates that the urban road network layout may significantly influence the general carbon footprint of post-flood pavement restoration. The carbon emissions from only restoring the main body of damaged pavements after this 70-hour disaster are estimated to offset almost 1% of the local decarbonization achievement for a month. Indirect carbon footprints from material production (67%) and delivery (29%) are much higher than direct emissions from on-site tasks (4%). Measures such as optimizing pavement materials, reusing wastes, rationalizing delivery routes, and improving the city layout help alleviate the burden of recovery. This study reflects on the environmental costs of disaster recovery processes, with a view to supporting improved mitigation strategies. The integrated modeling framework can also be applied to cities in different contexts to enrich reference for decision-making.

How to cite: Zhong, W., Howard, G., and Neal, J.: Estimating the carbon footprint of post-flood urban road network restoration: A case study in Carlisle, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-31, https://doi.org/10.5194/egusphere-egu24-31, 2024.

X4.169
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EGU24-15873
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ECS
Daniela Rodriguez Castro, Kasra Rafiezadeh Shahi, Nivedita Sairam, Melanie Fischer, Guilherme Samprogna Mohor, Annegret Thieken, Benjamin Dewals, and Heidi Kreibich

After the 2021 floods in Europe, independent data collection initiatives were undertaken in the impacted areas of Belgium and Germany. The resulting datasets at residential building level contain valuable information on hazard characteristics, vulnerability of exposed assets, socio-economic factors and coping capacity of the inhabitants and the emergency services (i.e., emergency and precautionary measures). A transnational analysis of these datasets enhances our understanding of flood damage mechanisms.

The data analysed resulted from 420, and 609 standardized surveys with private households affected by the 2021 floods in Belgium and Germany, respectively. Of these, 277 correspond to the area of Rhineland-Palatinate, and 332 were from North Rhine-Westphalia in Germany. A set of 64 potential damage influencing variables were harmonized across the datasets. The initial phase involved conducting descriptive statistics of the selected variables in three regions: the Vesdre valley in Belgium, the Ahr valley in Rhineland-Palatinate (Germany) and affected regions in North Rhine-Westphalia (Germany).

In a second step, the most influential variables for predicting flood damage to residential buildings were identified by means of feature selection. This was conducted using the linear approaches multilinear with k-best predictors, and Elastic net regression as well as the non-linear techniques Random Forest and Conditional Inference Trees. Total building loss and the total content loss were used as target values. Based on different evaluation metrics, the most important variables describing absolute building damage and absolute contents damage in the three analyzed areas, were identified.

Commonalities and differences in flood characteristics and damage in the three regions will be presented and interpreted in detail.

How to cite: Rodriguez Castro, D., Rafiezadeh Shahi, K., Sairam, N., Fischer, M., Samprogna Mohor, G., Thieken, A., Dewals, B., and Kreibich, H.: Machine-learning based feature selection for a regional flood damage model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15873, https://doi.org/10.5194/egusphere-egu24-15873, 2024.

X4.170
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EGU24-2761
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ECS
Chi-Tung Hung, Wen-Yen Lin, and Chun-Fang Liu

This study focusing on the vulnerability and resilience in the downstream areas of the Da-an river basin (Dajia district and Houli district) centeral Taiwan. The study addresses the urban governance on compound disaster in the upstream Da-an river basin, including Taian township and Jhunan township in Miaoli county, Zhuolan township, and the Heping district in Taichung city. The research also explores how these townships adapt to extreme weather impacts and post-pandemic industrial adaptation. Our research employs various methods such as field surveys, in-depth interviews, literature reviews, and statistical data analysis: (1) By investigating and analyzing tourism camping areas in the aforementioned townships, we examine the environmental vulnerability of their industries and land use. This includes environmentally sensitive areas and agricultural and pastoral lands in indigenous areas, as well as issues related to vulnerable policies; (2) Agricultural production and marketing and government responses to different stages of impacts from extreme climates and diseases are being reviewed regarding the adaptive planning of local governments; (3) A vulnerability assessment framework applicable to settlements in islanding areas of the upper Da-an river is constructed by utilizing the Analytic Hierarchy Process (AHP) and Geographic Information System (GIS) for overlay analysis to discuss the relevant assessment influencing factors in camping areas. The research aims to clarify how watershed townships, under the influence of climate change, transform based on local tourism characteristics and agricultural industries post-pandemic. Particularly, it explores the mitigation measures demonstrated by local governments and private operators in the face of climate change and land exposure, showcasing the resilience of governance at different levels of government and private entities. Two aspects are found on this research: (1).The tourism vulnerability of townships in the upper Da-an river basin, particularly the crisis of camping tourism sites and land exposure, along with the island effect of their settlements. (2). Adaptive mechanisms of industrial resilience in watershed townships under the impact of the pandemic.

Keywords: river basin, extreme weather, islanding effect, city resilience, urban disaster, city vulnerability.

How to cite: Hung, C.-T., Lin, W.-Y., and Liu, C.-F.: The islanding effect of river basin city-regions under climate changes: vulnerability and resilience, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2761, https://doi.org/10.5194/egusphere-egu24-2761, 2024.

X4.171
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EGU24-7335
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ECS
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Ashish Kumar and Udit Bhatia

Floods are among the most costly natural disasters globally and are projected to increase in frequency and magnitude with a warming climate. To confront increasing flood risks, flood managers need the most cost-effective adaptation actions to reduce economic damage to floodplain infrastructures. Recent research advancements have explored the physical aspects of flood adaptation strategies such as levees, diversions, and barrages. However, implementing adaptation actions requires comprehensive economic analysis before execution due to the substantial capital investment involved. Here, we develop a 1D-2D coupled hydrodynamic flood model in the MIKE+ platform, considering river flow to generate flood inundation maps for various hydraulic inland scenarios. We generate inundation maps for 10-, 50-, 100-, and 200-year return periods of design discharge, considering flood adaptation strategies. Subsequently, we utilize available flood depth-damage functions to calculate expected flood damage and conduct a cost-benefit analysis of the proposed adaptation strategies. We demonstrated the proposed framework for the coastal city of Surat, India. Our results provide the decision matrix to select adaptation strategies based on design standard objectives. The initial assessment highlights that a combination of levee and barrage is more effective than individual levee, barrage, and diversion strategies, particularly in terms of cost-effectiveness in reducing flood damage. Our framework would be beneficial in selecting effective planning strategies for reducing flood damage.

How to cite: Kumar, A. and Bhatia, U.: Evaluating Flood Adaptation Effectiveness through Economic Analysis: A Case Study of Surat, India, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7335, https://doi.org/10.5194/egusphere-egu24-7335, 2024.

X4.172
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EGU24-6859
Mo-Hsiung Chuang, Shyue-Yen Lin, Kuo-Chen Ma, and Cheng-Yu Ku

This study aims to explore the assessment of landslide hazards and adaptation faced by coastal communities under the impact of climate change. Considering the influence of climate change leading to increased frequency of extreme weather events, particularly heavy rainfall, which significantly affects the stability of hill slopes, this research will establish a shallow landslide susceptibility model for extreme rainfall events. This model can comprehensively solve the unsaturated transient Richard's equation and utilize the resultant pore water pressure along with the formula for the safety factor of unsaturated slope stability to construct a comprehensive regional landslide susceptibility analysis module. The module will generate distribution maps depicting the potential for slope collapses during extreme rainfall events. Through this analysis module, the study intends to predict collapse grids influenced by climate change and use Geographic Information Systems to create collapse susceptibility maps. We will overlay these maps with key infrastructure of coastal communities, including emergency response units, to understand the impact of landslide disasters on the infrastructure, emergency response capabilities during disasters, and post-disaster recovery capabilities of coastal communities. Furthermore, the study will explore the impact and adaptation strategies of climate change on infrastructure in coastal communities.

How to cite: Chuang, M.-H., Lin, S.-Y., Ma, K.-C., and Ku, C.-Y.: Study on the impact and adaptation strategies of climate change on infrastructure in coastal communities., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6859, https://doi.org/10.5194/egusphere-egu24-6859, 2024.

X4.173
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EGU24-9505
The Effect of Natural Hazard on Residential Housing Prices: a Hedonic Difference-in-Differences Analysis of a Flooding Event in Southern Taiwan
(withdrawn after no-show)
Yaowen Hsu, Shih-Ping Ho, and Christina C. W. Tsai
X4.174
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EGU24-10972
Mohammad Heidarzadeh, Mahan Sheibani, and Roberto J. Luis-Fonseca

Recent years have seen a rise in both the intensity and frequency of storms, resulting in damage to coastal protection systems across the UK and globally. As a result, these systems have demanded substantial maintenance. For example, the gabion protection at Chesil Beach (Portland, UK) was severely damaged during the storms of February 2014, necessitating restoration costing at least £600 million. Similarly, the rock armor protection at Beesands (Devon, UK) also suffered damage in the same storm. These incidents highlight the urgent need to develop more resilient and innovative coastal defense systems. This fact gains further significance considering the UK's extensive coastal defense sector, necessitated by its vast coastlines with a length of approximately 30,000 km. According to various sources, approximately 18% of UK coastlines are protected with defense systems.

Here, we introduce an innovative coastal defense system comprising high-strength steel-wire mesh filled with rock. The system is securely fastened using tension rod ensuring its long-term integrity and stability. The diamond mesh in this system features units measuring 8.3 cm in width and 14.3 cm in height. These units are filled with uniformly-sized rock units, typically ranging in diameter from 15 cm to 25 cm. The high-tensile stainless-steel mesh, referred to as 'Tecco Cell’, is supplied by Geobrugg Inc. Therefore, we name this system as Tecco Cell (TC) revetment hereafter. The TC revetment carries the advantages of both gabion and rock revetments and minimizes their drawbacks. Gabion baskets or mattresses are susceptible to a significant weakness: their wire baskets can be damaged or broken by the force of strong waves. For rock armor, the rock units are displaced by strong waves resulting in the collapse of the defense system. The TC revetment systems alleviate both drawbacks; their high-strength mesh resists waves, while the tension rods, combined with the mesh, stabilize the system even against the strongest waves. The TC revetment was installed along a 120-meter stretch of the coast in Beesands (Devon, UK) in 2016. Over the past seven years, it has effectively defended the coast with minimal maintenance needs. Despite encountering several winter storms since its installation in 2016, the TC system in Beesands has remained resilient.

The purpose of this research is to report the results of two phases of laboratory tests on a 1/10 scaled model of a TC revetment. In Phase 1, eight tests were delivered on three types of revetments: gabion (two tests), rock armor (two tests) and TC revetments (four tests). In Phase 2, we conducted 32 tests comparing TC (16 tests) and rock armor (16 tests) revetments. It was found that the TC revetment consistently outperformed rock armor in terms of run up control and wave oscillations with an average runup reduction of 15%. We developed empirical equations for wave runup.

Thanks to the successful implementation of the TC revetment in Beesnads (UK), there is now consideration for applying this new coastal defense system in Ritoque (Chile) and along the northwestern coast of Italy.

How to cite: Heidarzadeh, M., Sheibani, M., and Luis-Fonseca, R. J.: A new revetment system based on high-strength steel-wire mesh filled with rock for coastal erosion control, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10972, https://doi.org/10.5194/egusphere-egu24-10972, 2024.

Posters virtual: Thu, 18 Apr, 14:00–15:45 | vHall X4

Display time: Thu, 18 Apr, 08:30–Thu, 18 Apr, 18:00
Chairpersons: Maria Bostenaru Dan, Nurullah Bektaş
Geophysical hazards
vX4.36
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EGU24-10164
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Highlight
Maria Mavrouli, Spyridon Mavroulis, Emmanuel Vassilakis, Ioannis Argyropoulos, Panayotis Carydis, and Efthymios Lekkas

Disasters arising from geophysical hazards have the potential to trigger extensive structural damage upon the built environment within the impacted area. A substantial proportion of debris generated from earthquakes is a consequence of structural collapse during the ground motion, coupled with the urgent demolition of severely damaged and unstable structures in the course of emergency response and recovery. Among the foremost and pivotal measures undertaken during disaster management is the effective management of the generated debris. This task stands as one of the paramount challenges faced by those involved, given its inherent hazards to both the natural environment and public health. These hazards emanate from the presence of hazardous materials within debris from collapses and demolitions.

Numerous challenges and associated hazards emerged in southeastern Turkey after two devastating earthquakes on 6 February 2023 with Mw=7.8 and Mw=7.5 respectively. These seismic events affected a densely populated region encompassing 11 provinces, which included numerous sizable urban centers, such as large cities and towns, along with extensive rural areas comprising countless villages.

The convergence of intense ground motion, accompanied by the occurrence of widespread primary effects, such as coseismic surface ruptures, and the triggering of secondary effects, including mainly but not limited to liquefaction and landslides, culminated in the total or partial collapse of tens of thousands of structures and the extensive leveling of residential areas. This fact gave rise to a debris volume deemed the largest since the 1994 Northridge earthquake and challenging to manage, even within well-organized nations.

In the course of post-event field surveys conducted by the authors within the earthquake-stricken area, various disposal sites established in the most severely affected provinces were identified and assessed for suitability. The field surveys included the utilization of Unmanned Aircraft Systems (UAS) in the disaster-affected areas, complemented by the examination of satellite imagery in the laboratory to evaluate the characteristics of the sites and their immediate surroundings and to monitor the ongoing debris management activities.

The findings indicate that none of the identified sites possessed attributes qualifying them as safe for the treatment and disposal of earthquake debris. Primarily, this inadequacy is attributed to their close proximity to areas densely populated with thousands of residents who engage in daily activities. Furthermore, from the environmental viewpoint, these sites operated either within or in close proximity to surface water bodies. This situation reveals a rush for rapid debris removal and recovery resulting in serious omissions in the preparation of disaster management plans and concessions in their implementation. Consequently, recommendations for effective debris management measures are also proposed in the context of this research based on existing scientific knowledge and operational expertise.

How to cite: Mavrouli, M., Mavroulis, S., Vassilakis, E., Argyropoulos, I., Carydis, P., and Lekkas, E.: Debris Management in the Area Affected by the 6 February 2023 Turkey Earthquakes: Detecting Challenges, Hazards and Responses aiming to Effective Disaster Risk Reduction, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10164, https://doi.org/10.5194/egusphere-egu24-10164, 2024.